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MySQL, better to insert NULL or empty string?
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221
By using NULL you can distinguish between "put no data" and "put empty data".
Some more differe...
getting date format m-d-Y H:i:s.u from milliseconds
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15 Answers
15
Active
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Rails formatting date
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Use
Model.created_at.strftime("%FT%T")
where,
%F - The ISO 8601 date format (%Y-%m-%d)
%T - 24-hour time (%H:%M:%S)
Following are some of the frequently used useful list of Date and Time formats that you could specify in strftime method:
Date (Year, Month, Day):
%Y - Year with cent...
Why does this iterative list-growing code give IndexError: list assignment index out of range?
...ample below), and later, overwrite the values in specific positions:
i = [1, 2, 3, 5, 8, 13]
j = [None] * len(i)
#j == [None, None, None, None, None, None]
k = 0
for l in i:
j[k] = l
k += 1
The thing to realise is that a list object will not allow you to assign a value to an index that doe...
How do I put double quotes in a string in vba?
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187
I find the easiest way is to double up on the quotes to handle a quote.
Worksheets("Sheet1")....
Using querySelector with IDs that are numbers
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109
It is valid, but requires some special handling. From here: http://mathiasbynens.be/notes/css...
Deep copy of a dict in python
... }
d2 = copy.deepcopy(d)
Python 2 or 3:
Python 3.2 (r32:88445, Feb 20 2011, 21:30:00) [MSC v.1500 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import copy
>>> my_dict = {'a': [1, 2, 3], 'b': [4, 5, 6]}
>>> my_copy =...
How to fallback to local stylesheet (not script) if CDN fails
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11 Answers
11
Active
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Boost.Asio的简单使用(Timer,Thread,Io_service类) - C/C++ - 清泛网 - 专注C/C++及内核技术
...的头文件.所有的asio类可以简单的通过include "...目录：
1. 同步Timer
2. 异步Timer
3. 回调函数的参数
4. 成员函数作为回调函数
5. 多线程回调同步
6. TCP客户端:对准时间
7. TCP同步时间服务器
1. 同步Timer
本章介绍asio如何在定...
PHP Pass by reference in foreach [duplicate]
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146
Because on the second loop, $v is still a reference to the last array item, so it's overwritte...